The invention relates generally to surface mounted connectors on printed circuit boards, and more specifically to a repairable contact for a ball grid array connector.
The ongoing trend toward smaller, lighter, and higher performance electrical components and higher density electrical circuits has led to the development of surface mount technology in the design of printed circuit boards. As is well understood in the art, surface mountable packaging allows for the connection of an electronic module, or package, to pads on the surface of the circuit board rather than by contacts or pins soldered in plated holes going through the circuit board. Surface mount technology allows for an increased component density on a circuit board, thereby saving space on the circuit board and/or allowing for reductions in board size.
The ball grid array (BGA) is one particular type of surface mount package that has been developed in response to the demand for an increased density of electrical connections on the circuit board. The ball grid array includes an array of connections on the bottom side of the connector. In the ball grid array, pins extending into the circuit board are replaced by small solder balls placed on the bottom side of the connector at each contact location. The circuit board, rather than holes, has an array of contact pads matching the solder ball placements on the connector bottom. Connections are made by reflowing the solder balls to mechanically and electrically engage the connector to the circuit board.
BGA technology offers the advantages of higher connection densities on the circuit board and higher manufacturing yields which lowers product cost. However, BGA technology is not without disadvantages. For instance, solder joints cannot be easily inspected, and circuit board level rework, i.e. correcting problems after attachment of the BGA package to the circuit board, is more difficult since, having no replaceable components, the BGA connectors are typically unserviceable.
Thus, a need exists for a ball grid array connector that is serviceable after the ball grid array package has been reflowed onto the circuit board.